<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<style type="text/css">
#container {
	position: relative;
}

#box1 {
	position: absolute;
	top: 100px;
	left: 210px;
	width: 200px;
	height: 200px;
	background-color: yellow;
	z-index: 5;
}

#box2 {
	position: absolute;
	top: 50px;
	left: 160px;
	width: 200px;
	height: 200px;
	background-color: green;
	z-index: 10;
}
</style>
</head>
<body>
	<div id="container">
		<div id="box1">这个box应该在上面</div>
	</div>

	<div id="box2">这个box应该在下面，IE浏览器会对定位元素产生一个新的stacking context
		，甚至当元素 z-index的为“auto”。</div>
</body>
</html>